approximate.py 文件源码

def _generate_masks(self):
        """Creates left and right masks for all hash lengths."""
        tri_size = MAX_HASH_SIZE + 1
        # Called once on fitting, output is independent of hashes
        left_mask = np.tril(np.ones((tri_size, tri_size), dtype=int))[:, 1:]
        right_mask = left_mask[::-1, ::-1]

        self._left_mask = np.packbits(left_mask).view(dtype=HASH_DTYPE)
        self._right_mask = np.packbits(right_mask).view(dtype=HASH_DTYPE)